1. Field of the Invention
The present invention relates to an air pump apparatus, and in particular to an air pump nozzle for engaging with an inflation valve of an inflatable object.
2. The Prior Arts
Inflation valves are universally found installed on inflatable objects, such as tires. When inflation is needed, the inflation valve is engaged with a nozzle fastened to an air hose to allow air to be pumped into the inflatable object.
A conventional inflation valve is provided with a valve needle. When the valve needle is in a standby position, the air pressure inside the inflatable object seals the air valve and prevents the air from leaking out. When the valve needle experiences an external force, the valve is opened up, which enables the inside of the inflatable object to communicate with the atmospheric air and allows air to be discharged from or charged into the inflatable object.
In general, there are two methods to inflate an inflatable object. One is to engage a nozzle fastened to a hose with the inflation valve of the inflatable object. The hose is in turn connected with an air pump or an air compressor, so that air is pumped through the hose and the nozzle into the inflatable object. The other method is to engage the nozzle directly disposed at an air outlet of the air pump with the inflation valve, so that air may be pumped through the nozzle into the inflatable object.
FIGS. 6 and 7 illustrate the structure of a conventional air pump nozzle, which comprises a housing A, whose inner space holds a needle tube E, a sleeve body D, and a block member C, and a cap B which closes the inner space of the housing A. The needle tube E is received in the block member C, which as a whole is received in the sleeve body D. A first end E1 of the needle tube E protrudes through the housing A to be connected with a hose. When the cap B is engaged with the air valve of the inflatable object, a second end E2 of the needle tube E repels against a valve needle inside the air valve, and opens the air valve to allow air to be filled in from a central hole E4.
The conventional needle tube E is structured with a tubular body having a protruded edge E3 formed at a proper position in its outer periphery. The protruded edge E3 divides the needle tube E into the first end E1 and the second end E2. The first end E1 is to be connected with a hose, while the second end E2 is to be pressed against the air valve of an inflatable object. The housing A has to be capable of rotating freely around the needle tube E in order to engage the cap B connected to the housing A with the inflation valve. To fulfill the requirement, the metal sleeve body D is disposed covering the block member C and part of the needle tube E to avoid the friction between the rubber block member C and an inner periphery of the housing A from hindering the housing rotation.